case pattern with instanceof pattern


Change-Id: Iba22aee8a210a3df5fcaee6eaf0699df7f3b069e
Signed-off-by: Jay Arthanareeswaran <jarthana@in.ibm.com>
Also-By: Stephan Herrmann <stephan.herrmann@berlin.de>
Reviewed-on: https://git.eclipse.org/r/c/jdt/eclipse.jdt.core/+/190216
Tested-by: JDT Bot <jdt-bot@eclipse.org>